Conventionally, in a power module that performs power conversion and control, electrical connection and heat dissipation to a substrate have been realized by connecting one side of a chip onto the substrate with solder and connecting the other side of the chip to the substrate via wire bonding.
However, in response to a growing demand for size reduction of power modules as well as an increase in the heat dissipation amount, a method for connecting both the front and rear sides of a chip with solder and cooling the chip from the opposite sides thereof has been adopted. FIG. 1 shows an example of such module that adopts a structure in which a chip 1 is cooled from the opposite sides thereof using lead frames 3 and fins 5.
Such a heat dissipation method is also adopted in Patent Literature 1 to 3. Such a double-side cooled power module is formed by sealing the components with molding resin after solder connection and then providing cooling portions on the outer side of the components.